Manufacture of black vat dyestuffs.



' .EDWARJD WRAY, 01E BIEBRICH, GERMANY, ASSIGNOR 1'0 THE FIRM F KALLEAND CQMPANY, AK'IIENGESELLSCHAFT, 0F BIEBRICH, GERMANY.

MANUFACTURE OF BLACK VAT DYJES'IUFFS.

To all whom it may concern:

Be it known that I, EDWARD WRAY, chem ist, and a subject of the King ofEngland, residing at 2 Kaiserstrasse, Biebrich-on-the- Rhine, Germany,have invented certain new and useful Improvements in the Manufacture ofBlack Vat Dyestuffs, of which the tives.

N Cl H These dyestufl's have the following graphically representedformula, in which It stands for a mono-chlor-isatin radical:

The production of this dye-stuff is technically more advantageousbecause the parachloro-isatin-alpha-para-chloro-anilid can bemore easilyroduced than the di-bromoisatin-alpha-amlid. Furthermore the dyestufipossesses in reduced state a greater solubility giving a clear vat,whereas the d estufi obtained from di-bromo-isatina pha-anilid gives derthe same condi- Speciiication of Letters Patent.

Application filed July 17, 1913. Serial No. 779,636.

Patented @ct. I9, ftllllfi.

tions a more dificultly soluble leuco-compound.

It was not to have been expected that the dye-stud obtained according tothe present invention, which contains only one chlorinatom, wouldpossess more valuable properties than the dye-stuff described in GermanLetters Patent No. 241997 which contains two bromin-atoms.

In order to illustrate the process more fully I can proceed as follows,the parts being by weight: 14 parts ofpara-chloroisatin-alpha-para-chloro-anilid, 6 parts of5-oXy-2.l-naphtho-carbazole and 70 parts of acetin-anhydrid are boiledtogether until the formation of the dye-stuff is complete. After coolingto about 70 centigrade the condensation product which has separated outis filtered and Washed with hot glacial acetic acid and alcohol. The newcoloring matter has the following formula III and, when dry, is a blackpowder which is insoluble in water and alcohol, soluble in hotnitro-benzene and quinolin with a blue color and in cold sulfuric acidwith a slateblue color. It yields on treatment with hydrosulfite andalkali a clear yellow vat from which cotton is dyed yellow changing onexposure to air into a fast black.

I claim:

1. A process for producing black vat dyestuffs which consists incondensing monochloro-isatin-alpha-derivatives withphenooxy-naphtho-carbazole of the following formula,

2. A process for producing black vat dye stufis which consists incondensing parachloro-isatin-alpha-para-chloro-anilid withpheno-oxy-naphtho-carbazole of the following formula,

in the presence of acetic anhydrid.

4. A process for producing black vat dyestufls which consists in heatingin the presence of acetic anhydrid,mono-chloro-isatina1pha-para-chloro-analid withpheno-oxynaphtho-carbazole, of the following formule:

5. As new products black vat dye-stuffs obtainable by combiningmono-chloro-isatinalpha-derivatives with a pheno-oxy-naphtho-carbazole'derived from alpha-naphthylamin, said products having the followinggraphically represented formula:

=l l l k l in which formula R stands for a monochlorisatin radical.

6. As a new product 5-chloro-2-indol-6-phenyl-alpha-naphthylcarbazolindigo of the following formula:

Cir

. being a blackrpowder in dry state, insoluble in water and alcohol,soluble in hot nitrobenzene and quinolin with a blue, in cold sulfuricacid with a slate-blue color, forming when reduced with alkalinereducing agents a clear yellow vat from which the textile fiber is dyedin fast black shades.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

EDWARD WRAY.

Witnesses:

MoRrrz VVEZEL, MINNA RrrzsL.

